Automatic throttle-valve-locking mechanism for pneumatic tools.



, R. A. NORLING. AUTOMATIC THROTTLE VALVE LOOKING Mnonamsm FOR PNEUMATICTOOLS.

' APPLICATION FILED MAE-8. 1910.

1 ,O27,06 1 Patented May 21, 1912.

@WUWQY "UNIE STATES PATENT OFFICE.

REINH'OLD A, NORLING, OF AURORA, ILLINOIS, ASSIGNOR TO AURORA AUTOMATICMACHINERY COMPANY, OF AURORA; ILLINOIS, A CORPORATION OI? ILLINOIS.

AUTOMATIC THROTTLE-VALVE-LOCKING MECHANISM FOR PNEUMATIC TOOLS.

Specification of Letters Patent.

Patented May 21,1912.

Application filed March 8, 1910. Serial No. 547,978.

act description therco't. reference being bad, to the accompanyingdrawings, and to the lettcrs of reference marked thereon. which form apart oil this specification.

'lhis invention relates to a portable pneumatic hammer or device of thatclass embracing a barrel or c 'linder; a piston or plunger adapted toslide therein, and a controlling valve through which the air or otherfluid underpress'ure is admitted thereto and permitted to escape fromthe opposite end of the cylinder or barrel to give reciprocatorymovement to the plunger tl'ierein. Air is supplied to the controllingvalve by means of a throttle valve which is so located that it may bereadily manipulated by the user of the hammer.

The invention relates to the means for operating the throttle valve andparticularly to an automatic locking device which is adapted to locksaid means in position to hold the throttle valve .in open position.

It consists of the combination of parts hereinafter described and moreparticularly pointed out. in the appended claim.

In the drawings:-.l*igurc l is a section through the handle end of apneumatic hammer, taken on a plane containing the axis t' the handle andthe axis of the throttle valve chamber. l ig. 2 is a partial sectionthrough Fig. 1 on the line 9-2 thereof. Fig. 3 is a similar section withthe parts shown in a different position.

In the embodiment ot my invention illus trated in the drawings, Aindicates the barrel or cylinder of the hammer; ll, the handle formed atthe inner end thereof, and preferably integral therewith: the throttlevalve chamber; D, the throttle valve stem; and I), the throttle valvedisk. The supply end of the throttle valve chamber is provided with aninternally screw-tln'eaded aperture into which is screwed a threadednipple E provided with a fixed ring r: in which is formed an aperture eto act as a guide for the outer end of the valve stem.

parts are of the usual construction and require no furtherdes(.=ription. The handle I and the barrel A are extended laterally toform parallel longitudinally extending ribs F," F which are separated bya slot or groove 7".

G indicates an operating lover or trigger which is pivoted at one endwithin the slot or groove f on a pin secured to the ribs I", ll. Thevalve stem Dprojccts between said ribs and is adapted to be engaged by arounded projection 9 formed on the underside of the lever G. Said leveror trigger provided .at its tree end with a laterally extending thumbpiece G. The opposite end of the lever is provided with a heel adaptedto engage against the bottom of the slot f and limit the upward movementof the trigger. It is apparent: that by pressipg on the thumb piece Gthe valve D will be depressed and the valve disk D dislodged from itsposition against its seat D'-.

The ribs F, F are provided with circular holes or openings K, K arrangedin line with each other and the rib F is provided with a second circularopening K parallcl to the common axis of the first two and above them.The side of the rib F is recessed to connect the outer ends of the holesK, K All of said holes open into the slot P. In the holes K, K islocated the long member I of the J-shaped rod L and in the hole K islocated the short member L of said rod. The curved member Z of the J-shaped rod lies in the recess connecting the openings K, K

The long member I of the bent rod L projects beyond the outer face ofthe rib F.

A cap M having a shank m, is secured to the end of said long member andthe hole K is enlarged throughout a portion of its length, as indicatedat In, to receive the inner end of said shank and also a coiled springis which bears against 'thc inner end of said shank and normally holdssaid, J-shaped rod with the curved member Z lying within the recess 7.2In this position. the beveled end I of the member If projects into theslot f and stands in the path of the lever or trigger G. Said trigger isprovided with a hole or opening g which is so located that when thetrigger is depressed, the axis of said opening will come into a positionin line with the axis of the member L The operation of the improvedlocking device is as follows :-When the lever G is, depressed by theoperator to open the throttle valve, the projection gon the lower edgeof said lever strikes the beveled end of the member L and pushes it outof the way. As soon as the opening g comes into line with the projectingend of the member L the action-of the spring 76 causes said end to enterthe hole 9 and thus lock the lever against upward movement, asillustrated in Fig 3, thereby maintaining the throttle valve in openposition. When it is desired to close the throttle, the trigger G isreleased byfpressing against the cap M which withdraws the end of themember L from the openings and permits the trigger to rise and releasethe throttle valve.

The devicedescribed herein is of simple and economical construction andis readily adaptable to any hammer of the kind referred to. It relievesthe workman of that muscular strain which is experienced in holding thethrottle open by hand or finger pressure, which, owing to the variationsof pressure, and the resultant vibration of the valve operatingmechanism, in addition to the vibration of the tool as a whole, operatesagainst the continuous use'of the hammer by the same workman'for long orextended periods of time.

While I ,have illustrated in the drawings one embodiment of myinvention, it is to be understood that I do not limit myself to thedetails of construction shown and described herein exceptas pointed outin the appended cla ms, as it is apparent that said mechani -al detailsmay be variously modified without departing from the spirit of myinvention.

I claim as my invention In a pneumatic hammer, the combination with abarrel provided with a transversely arranged handle on the inner eridthereof 5 and with longitudinal, outwardly extending, parallel ribslocated at one end of said handle, a normally closed throttle valve insaid barrel for controlling the supply of pressure fluid thereto, saidvalve being located adja- '55 cent to said handle, a stem for said valvearranged transversely of the barrel and projecting outwardly therefrominto the space between said ribs, a hand-controlled lever pivotallymounted between said ribs and adapted to act on said stem to open saidvalve, said handle being provided with a hole extending transverselythrough the same and with a second hole extending through. one of saidribs, parallel with and outside of the first-named hole, a catch memberconsisting of a U-shaped rod having rigidly connected long and shortlegs mounted and adapted to slide in said holes, the

shorter leg being located in the outermost hole and being-provided witha beveled end which normally projects into the path of said lever; saidlever being, provided with an opening adapted to be engaged by thebeveled end of said shorter leg, and the said longer leg projectinglaterally outside of the handle, and a spring adapted for yieldinglyholding said catch member in position for engagement of its-shorter legwith said lever.

In testimony that I claim the foregoing as my invention I afiix mysignature in the presence of two witnesses, this 25th day of February A.D. 1910.

' REINHOLD A. NORLING.

Witnesses:

CLARK EAGLETON, JAMES R. BRADSHAW.

